Combined process to produce both a pipelineable crude and carbon fiber from heavy hydrocarbon

ABSTRACT

An integrated process that is operated to create both a higher value pipelineable crude and a higher value carbon fiber product from a lower value common heavy hydrocarbon feedstock where the feedstock is processed in a thermal reactor followed by a solvent deasphalting unit with the liquids being gathered and processed to reduce olefins for pipeline transport and the solids are processed to generate a marketable carbon fiber product with any gases generated throughout the entire process reused in the process or sold.

FIELD OF THE INVENTION

The invention disclosed and claimed has to do with processing of heavyhydrocarbon feedstock such as Canadian bitumen (but any heavyhydrocarbon) to upgrade the feedstock to marketable and transportableproducts, such as blended crude oil suitable for transport by pipelineand value-added carbon fibre or carbon-fibre precursor materials. Theinvention is a type of hydrocarbon upgrading process or system.

PRIOR ART

The following discussion is meant to inform the reader of the state ofthe art in the realm of this invention.

U.S. Pat. No. 4,454,023 discloses a method that thermally cracks a heavycrude and solvent deasphalts the residue into a liquid pitch using asolvent process. A lower yield pipelineable crude product is created andthe process creates a liquid phase asphaltene by-product that is thensent to a gasifier for combustion purposes.

U.S. Pat. No. 4,572,281 provides a process to generate solid asphaltenespost-solvent deasphalting from heavy hydrocarbon. The generation of thesolid asphaltenes occurs at a different point in the process, theasphaltene solids are considered for combustion, and there is no mentionof a pipelineable crude as a product.

U.S. Pat. Nos. 9,200,211 and 9,150,794 both disclose a method togenerate pipelineable crude while producing a solid asphaltene productthat is generated as a solid in the mixing portion of the solventdeasphalting step. However, these patents do not address anything beyondsolid asphaltene products made in concert with the pipelineable heavycrude, and simply teach that the solid asphaltene material is good foruse in combustion processes like gasification and for power production.

U.S. Pat. No. 7,101,499 shows an apparatus for producing pellets fromhot heavy hydrocarbon or asphaltene that supplies the hot heavyhydrocarbon or asphaltene through a conduit to its outlet; and pelletproducing medium or means that breaks up the liquid stream of the hotasphaltene flowing out of the outlet of the conduit and produces pelletsof asphaltene. The feedstock in this patent is a liquid asphalteneteaching away from the a solid being fed to the extruding step.

U.S. patent application 2013/0036714 is a continuous process forfractioning, combining, and recombining asphalt sources into asphaltcomponents for pelletization of asphalt and asphalt-containing productssuch that the pellets formed are generally uniform in dimension, freelyflowing, free from agglomeration, and the pelletized asphalt is driedand/or packaged, and preferably compatibly packaged, for additionalprocessing and applications. This patent requires a pre-pelletizingprocess (i.e. filtering) and a drying and/or packaging step. Also, thepatent refers to the Asphalt as a solid or liquid requiring filteringand heating/cooling to obtain the necessary viscosity and consistencyfor feed to the pelletizer. The feedstock to the transport preparationstep (i.e pelletizing) is essentially a liquid (with a softening point)teaching away from a solid particulate asphaltene product beinggenerated in the asphaltene removal step.

U.S. Pat. No. 9,580,839 makes carbon fiber from asphaltenes obtainedfrom heavy oil feedstocks undergoing upgrading in a continuous cokingreactor. The liquid-phase asphaltene stream is mixed as the asphaltenestream travels horizontally from a first end of a continuous cokingreactor. The process then takes the liquid-phase asphaltene streamthrough a filter to yield a purified asphaltene stream; introducing thepurified asphaltene stream through a spinneret to yield carbon-basedfilaments; passing the carbon-based filaments through an inert gasstream to yield a carbon-based fiber; and collecting the carbon-basedfiber on a draw-down device. The patent teaches away from using solidasphaltenes, as the feed to the spinneret is a liquid, and in additiondoes not produce a pipelineable crude from the process.

Applicant has found no patents or literature that disclose a common baseprocess to treat or upgrade a heavy hydrocarbon to produce two highervalued products that include a pipelineable heavy crude and a carbonfiber and/or activated carbon.

SUMMARY OF THE INVENTION

It is to be understood that other aspects of the present invention willbecome readily apparent to those skilled in the art from the followingdetailed description, wherein various embodiments of the invention areshown and described by way of illustration. As will be realized, theinvention is capable for other and different embodiments and its severaldetails are capable of modification in various other respects, allwithout departing from the spirit and scope of the present invention.Accordingly, the drawings and detailed description are to be regarded asillustrative in nature and not as restrictive.

In an embodiment, an integrated process is provided to produce both apipelineable crude and a carbon fiber product from a common heavyhydrocarbon feedstock, where the feedstock is first processed in athermal reactor and some of the product from the reactor is treated in asolvent deasphalting unit, with produced liquids being collected andmixed and further processed to reduce olefins, to produce a liquid crudestream for pipeline transport. From the same reactor product, asphaltenesolids are also produced from the solvent deasphalting unit, and thenfurther processed into a carbon fiber product, and gases generated atany portion of the entire process may be reused in the process or sold.This embodiment features the following specific ordered process steps:

-   -   a. Introducing heavy hydrocarbon feedstock to a heater and        raising the feedstock's temperature to a desired range below the        cracking temperature of the feedstock (600-660° F. (315.6-348.9°        C.));    -   b. Sending the heated heavy hydrocarbon feedstock for processing        to in a near atmospheric thermal reactor operating at an        elevated uniform bulk liquid temperature of 700-790° F.        (371.1-421.1° C.) for an in-reactor residence time (1 min to 7        hours) to create and produce a vaporized lighter heavy        hydrocarbon stream from the reactor and a separate heavier        liquid hydrocarbon stream from the reactor;    -   c. Condensing the lighter hydrocarbon stream produced from the        reactor in step b);    -   d. Saturating olefins in the condensed lighter hydrocarbon        stream from step c);    -   e. Mixing the heavier liquid hydrocarbon stream produced in        step b) with a lighter hydrocarbon which acts as a solvent to        precipitate asphaltene solid particulate (powder) which is and        remains solid at operating conditions, creating and producing a        solid/liquid mixture;    -   f. Separating the solid/liquid mixture produced in step e) into        two streams: a solid/solvent slurry and a second heavy        hydrocarbon liquid (resin)/solvent mixture;    -   g. Separating the heavy hydrocarbon liquid (resin)/solvent        mixture produced in step f) into a heavy hydrocarbon stream and        a solvent stream for reuse as required in process step e)    -   h. Mixing the heavy hydrocarbon stream produced in step g) with        the condensed lighter hydrocarbon stream produced in step d) to        create a pipelineable crude;    -   i. Separating solids from solvent in the solid/solvent slurry        produced in step f) in a solid/vapor inertial separation unit,        to produce a solvent-free solid asphaltene particulate (powder)        stream and a vaporized solvent stream where the vaporized        solvent is then condensed and reused as required in step e);    -   j. Adding a different solvent to the solid asphaltene powder in        step i) to create and produce a reduced solid stream primarily        consisting of coke, coke precursors and inorganic material and a        second stream being a mixture comprised of the added different        solvent and a reduced asphaltene solid particulate with coke,        coke precursors and inorganic material removed;    -   k. Separating the solvent/asphaltene mixture produced in step j)        to create and produce a stream of the different solvent which        may be reused as required in step j) and a reduced asphaltene        solid particulate stream;    -   l. Extruding the reduced asphaltene solid particulate produced        in step k) into non-Newtonian flowing fluid producing extruded        asphaltenes;    -   m. Spinning the extruded asphaltenes into continuous thread that        can be wound on a spool;    -   n. Stabilizing the spooled asphaltene thread by heat treatment        at 350-550° F. (176.7-287.8° C.) for up to 1 hour;    -   o. Carbonizing the stabilized asphaltene thread by heat        treatment at 1832-3632° F. (1000-2000° C.) for up to 1 hour to        produce a carbonized carbon fiber; and    -   p. Adding surface treatment and sizing the carbonized carbon        fiber to create a general purpose carbon fiber product.

In another embodiment, the process has an additional intermediateprocess step before step j) to produce a higher quality carbon fiberwith the following qualities:

-   -   Tensile strength of at least 1.5 GPa; and    -   Young modulus of at least 290 GPa,

the added process being an additional solvent separation step to removeinsolubles from the asphaltene powder solids in step i) which insolublemight hinder the formation of “marketable” carbon fiber thread.

In another embodiment of the process an additional step of flashseparation, preferably under partial vacuum, is performed to removelighter molecules from the asphaltenes before step j) in order to reducethe production of voids in the carbon fiber thread.

An additional step of graphitization may be added in yet anotherembodiment of the process after step m) to heat the carbon fiber to over5432° F. (3000° C.) to produce a graphene product.

Another embodiment of the process includes an additional thermalcracking step after step b) but before step e) to generate moremesophase material to improve the characteristics of the carbon fiberproduct.

An apparatus is provided in an embodiment of the invention to performthe steps of the above process as an integrated process to create both apipelineable crude and a carbon fiber product from a single crudefeedstock. The apparatus includes:

-   -   a. Means to introduce heavy hydrocarbon feedstock to a heater to        be raised to a desired temperature range below the cracking        temperature of the feedstock (600-660° F. (315.6-348.9° C.));    -   b. Means to send and process the heated heavy hydrocarbon        feedstock in a near atmospheric thermal reactor operating at an        elevated uniform bulk liquid temperature of 700-790° F.        (371.1-421.1° C.) for a desired residence time of between 1 min        to 2 hours to produce a vaporized lighter heavy hydrocarbon        stream from the reactor and a separate heavier liquid        hydrocarbon stream from the reactor;    -   c. Means to receive and condense the lighter hydrocarbon stream        in produced in b);    -   d. Means to saturate the olefins in the condensed lighter        hydrocarbon stream condensed in c);    -   e. Means to mix the heavier liquid hydrocarbon stream produced        in b) with a different lighter hydrocarbon acting as a solvent        to precipitate asphaltene solid powder at operating conditions        creating a solid/liquid mixture;    -   f. Means to separate the solid/liquid stream produced in e) into        two streams, one a solid/solvent slurry, and a second heavy        hydrocarbon liquid/solvent mixture;    -   g. Means to separate the heavy hydrocarbon liquid/solvent        mixture produced in f) into a heavy hydrocarbon stream and a        solvent stream that can be reused in e);    -   h. Means to mix the heavy hydrocarbon stream from g) with the        lighter hydrocarbon stream from d) to create a pipelineable        crude;    -   i. Means to separate the powder solids from the solvent in the        solid/solvent slurry produced in f) in an inertial separation        unit, creating a solvent-free solid asphaltene powder stream and        a vaporized solvent stream where the solvent may be further        condensed and reused in e);    -   j. Means to add a different solvent to the solid asphaltene        powder in i) to create a reduced solid stream primarily        consisting of coke, coke precursors and inorganic material and a        second stream comprised of the added solvent and asphaltene        solid mixture;    -   k. Means to separate the solvent/asphaltene mixture to create a        re-usable stream of solvent for use in j) and a reduced        asphaltene solid stream;    -   l. Means to extrude the asphaltene solids produced in k) into a        non-Newtonian flowing fluid producing extruded asphaltenes;    -   m. Means to spin the extruded asphaltenes into a continuous        thread that can be wound on a spool;    -   n. Means to stabilize the asphaltene-based thread at 400-500° F.        (204.4-260° C.) for up to an hour;    -   o. Means to carbonize the stabilized asphaltene thread at        1832-3632° F. (1000-2000° C.) for up to an hour; and    -   p. Means to add surface treatment and size the carbonized        asphaltene-based carbon fiber to create a marketable general        purpose carbon fiber product.

The apparatus may also include an additional solvent separation means toremove insolubles from the asphaltene powder solids from i) that mighthinder formation of “marketable” carbon fiber thread; similarly, theapparatus may include means to provide an additional step of flashseparation, preferably under partial vacuum, to remove lighter moleculesfrom the asphaltenes to reduce the formation of voids in the carbonfiber thread. Additional means to provide graphitization may be addedafter step m) for heating the carbon fiber to over 5432° F. (3000° C.)to produce a graphene product, and means to provide an additionalthermal cracking step may be included after b) but before e) to generatemore mesophase material to improve the characteristics of the carbonfiber product.

An integrated process is provided which is operated to create both ahigher value pipelineable crude and a high value carbon fiber productfrom a lower value common heavy hydrocarbon feedstock such as bitumen,where the feedstock is processed in a thermal reactor followed by adeasphalting step in a solvent deasphalting (SDA) unit, with liquidsproduced in the reactor and SDA being gathered and processed to reduceolefins and blended to make a crude liquid product for pipelinetransport, and with the asphaltene solids produced from the SDA beingprocessed to generate a marketable carbon fiber product, and with anygases generated throughout the entire process reused in the process orsold.

Pipelineable crude is defined as a crude that meets current pipelinespecifications of greater than API 19 (density <920 kg/m3), viscosityless than 300 cSt at reference temperature, sediment and water less than0.5 wt % and olefins less than 1 wt % or non-detectable by themeasurement tool used by the transporter.

Carbon fiber is defined as a fiber containing at least 92 wt % carbon.Carbon fibers generally have excellent tensile properties, lowdensities, high thermal and chemical stabilities in the absence ofoxidizing agents, good thermal and electrical conductivities, andexcellent creep resistance. They have been extensively used incomposites in the form of woven textiles, continuous fibers/rovings, andchopped fibers for making manufactured goods. The composite parts can beproduced through filament winding, tape winding, pultrusion, compressionmolding, vacuum bagging, liquid molding, and injection molding. Thisprocess creates both a pipelineable crude and commercial quality carbonfiber product.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram or flow-chart of the integrated process of theinvention.

FIG. 2 is a block diagram or flow-chart of a second embodiment of theintegrated process of the invention.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of various embodiments of thepresent invention and is not intended to represent the only embodimentscontemplated by the inventor. The detailed description includes specificdetails for the purpose of providing a comprehensive understanding ofthe present invention. However, it will be apparent to those skilled inthe art that the present invention may be practiced without thesespecific details.

FIG. 1 is a process flow diagram depicting a process 10 for forming ahydrocarbon liquid product 200, that meets pipeline specification and acarbon fiber product 120 from a common heavy hydrocarbon feedstock 5that cannot itself be shipped by pipeline without treatment ormodification. The final hydrocarbon product 200 has sufficientcharacteristics to meet minimum pipeline transportation requirements(minimum API gravity of 19, at least 350 cSt at 7.5° C., less than 0.5wt % sediment and water and olefins less than 1 wt % (ornon-detectable)) and is a favourable refinery feedstock while the finalsolid product 120 has sufficient characteristics to be used in generalpurpose and high performance carbon fiber products. Process 10 isdesigned to use over 95 wt % of the heavy hydrocarbon feedstock withover 83 wt % used as a pipelineable crude and over 12 wt % as carbonfiber.

As shown in FIG. 1, a heavy hydrocarbon feedstock 5, that can't beshipped via pipeline, can be routed through a heater 20 to heat thematerial to a desired temperature level and sent as stream 25 to areactor 30 where the process fluid temperature is controlled andmaintained while it undergoes a mild controlled cracking process. Sweepgas, 31, can be introduced into the reactor to assist in mixing theliquid pool in the reactor and to assist in removing any evolved vapoursfrom the hydrocarbon feedstock. The sweep gas can be any type ofnon-condensable vapour that can end up in the fuel gas system forcombustion or reuse in the process. Examples of sweep gas can be ahydrocarbon mixture such as natural gas or steam, nitrogen or hydrogen.After the mild cracking process, a light top fraction 33 can be routedfrom the reactor 30 to a gas liquid condensing separator and olefinsaturation process 40 with a heavy bottom fraction 32 routed to aliquid/solid solvent extraction process 50. The condensed overheadliquid fraction 33 will have a much higher API gravity than the bottomfraction 32. For example, the overhead liquid fraction 33 couldtypically have an API gravity of 26 or greater.

An olefin saturation process 40 takes the vapour stream 33 from thereactor 30 to convert the olefins in this stream to meet pipelinetransport specification. The condensed olefin-saturated liquid exitsunit 40 as stream 45 and can be blended into the final product, 200. Anynon-condensable vapour exits as stream 43 and can be sent to an H₂Sremoval unit, such as an amine unit, so vapour can be readily reused inthe process or used as a fuel gas.

Stream 32 from the reactor 30 is fed to the solvent deasphalting unit50. The solvent extraction process 50 can comprise any suitable solventextraction process that can handle the separation of precipitated solidsat operating conditions from the remaining hydrocarbon liquid. Anexample of a relevant solid-liquid solvent separation process is U.S.Pat. No. 9,976,093 and Canada patent 2,844,000. A recycled solventstream 63, 73 may be mixed with stream 32 to precipitate a solidasphaltene phase from the liquid 32 stream. Additional makeup solventmay be required to mix with stream 32 in separator 50. The asphaltenesprecipitated are a solid powder so a solid/liquid separation can now bemade as opposed to the typical liquid/liquid separation. A solid/liquidseparation requires less solvent to provide the desired recovery ofpipelineable heavy oil. A heavy deasphalted oil leaves the SDA unit, 50,as stream 57. Stream 57 is blended with stream 45 to create the finalproduct, 200, which has physical characteristics which enable it to meetrequired pipeline transport criteria without having to mix the finalhydrocarbon with transport diluents. The solvent used in SDA 50 can be apure hydrocarbon component ideally in the range of C₆ to C₈ or morepractically, a mixture of C₅ to C₈ extracted from readily availablenatural gas condensate or diluent that comes in with the heavy crudefeed.

Stream 53 contains entrained solid asphaltene powder in a solvent liquidphase. Stream 53 is reduced in pressure to flash the solvent to create avapor/solid mixture as a slurry or suspension that enters the inertialseparation unit (ISU), 60, for a solid/vapour separation. Solvent vapouris condensed and returned to the SDA unit 50 for reuse as stream 63. Theasphaltene solid powder leaves the ISU as stream 67 and enters anextruder to apply pressure to the solid asphaltenes to remove anyremaining entrained solvent. The extruder temperature can be in the200-350° C. range to create conditions to provide continuous flow as aNon-Newtonian fluid through and out of the equipment. The removedsolvent is returned to the SDA unit as stream 73. Some of the generatedasphaltene extrudate can be segregrated and sent to the solid fuelsmarket, as stream 71, if the market for carbon fiber is saturated or noteconomic. As another embodiment, material in stream 71 can be sent tofor processing to become activated carbon. The majority of the extrudedasphaltenes leave the extruding unit, 70, as stream 75 and is fed to thespinning unit, 80, where “green” carbon fiber is produced as stream 85.“Green” fiber is a term used for hydrocarbon crude derived fiber thathas yet to be oxidized or carbonized, and is extremely fragile.) Thespinning of the “green” fiber can be accomplished by either melt or jetspinning. Ideally, the diameter of the “green” fiber is less than 15 um,preferably less than 10 um for commercial applications.

The “green” fiber is then stabilized in unit 90. Stabilization isaccomplished by heating the fibers in a forced air environment toprovide sufficient fresh oxygen to the fiber surfaces air attemperatures in the range of 200-300° C. Heating causes the spun fibersto pick up oxygen molecules on their surfaces to prevent the onset ofinter-fiber coalescence or melting and to promote good carbon yield inlater carbonization. Stabilization can take between a few minutes up toan hour or two. The stabilized fiber, stream 95, is then carbonized, inunit 100, under an inert environment (no oxygen) and is heated uniformlyup to approximately 1000° C., but can go up to 1800° C. to improve boththe fiber strength and Young modulus. The carbonizing step can takebetween a minute to up to an hour or two depending on the finalproperties desired. The lack of oxygen prevents the fibers from burningin the very high temperatures. As the fibers are heated, they begin tolose their non-carbon atoms, plus a few carbon atoms, in the form ofvarious gases including water vapor, ammonia, carbon monoxide, carbondioxide, hydrogen, nitrogen, sulfur, evolved metals such as nickel andvanadium and others. As the non-carbon atoms are expelled, the remainingcarbon atoms form tightly bonded carbon crystals that are aligned moreor less parallel to the long axis of the fiber. In a variant of thisprocess, two furnaces operating at two different temperatures are usedto better control the rate of heating during carbonization. Thecarbonized fiber leaves as stream 108 and can have surface treatment andsizing applied in unit 110. Surface treatment and sizing methods mainlyused are acid oxidation, resin addition, plasma treatment, rare earthtreatment, and/or gamma irradiation. Surface treatment leads to improvedcomposite properties due to the conditions of improved surface area ofthe fiber surface, chemical bonding and adhesion between fiber andmatrix. Surface treating and sizing is typically used since aftercarbonizing, the fibers have a surface that does not bond well withepoxies and other materials used in composite materials. To give thefibers better bonding properties, their surface is slightly oxidized.The addition of oxygen atoms to the surface provides better chemicalbonding properties and also etches and roughens the surface for bettermechanical bonding properties. Oxidation can be achieved by immersingthe fibers in various gases such as air, carbon dioxide, or ozone; or invarious liquids such as sodium hypochlorite or nitric acid. The fiberscan also be coated electrolytically by making the fibers the positiveterminal in a bath filled with various electrically conductivematerials. The surface treatment process must be carefully controlled toavoid forming tiny surface defects, such as pits, which could causefiber failure.

The final carbon fiber product, stream 120, is normally general purpose(GP) carbon fiber. This product, 120, has a higher value than either thehydrocarbon feedstock, 5, or the typical disposition for asphaltenes, asa solid fuel.

As an additional embodiment to FIG. 1, After the surface treatment, thefibers can be coated to protect them from damage during winding orweaving. This process is called sizing. Coating materials are chosen tobe compatible with the adhesive used to form composite materials.Typical coating materials include epoxy, polyester, nylon, urethane, andothers.

The coated fibers are wound onto cylinders called bobbins. The bobbinsare loaded into a spinning machine and the fibers are twisted into yarnsof various sizes.

Another embodiment, shown in FIG. 2 provides modification options to theprocess shown in FIG. 1 and described above in order to create an optionfor production of high performance carbon fibers along with generalpurpose carbon fiber and pipelineable crude. Unit 35 can be added toprovide additional thermal cracking to the residue portion of the crudeto generate more mesophase material from the thermally affectedasphaltene solid powder for the feed to the SDA, 50, as stream 37.Mesophase content is a contributor to high performance carbon fiber.

Unit 65 can be added to perform further treatment and separation of theasphaltene solids. Stream 64 is undesirable solids that hinder thegeneration of carbon fiber while stream 66 contains flowable hydrocarbonthat create voids in the carbon fiber. The material in stream 66 can beadded to the hydrocarbon liquid product stream, 200, if the pipelinespecifications can be maintained. Otherwise, stream 66 can be recycledto unit 30 for re-processing. Stream 64 can contain coke particlesgenerated in reactor 30 and/or inorganic material in the feed. Unit 65can contain a second solvent deasphalting step using organic solventsthat adsorb heavier molecules than what is used in SDA unit, 50. Thesolvents that could be used to reject the heaviest, most undesirablesolids in the solid asphaltene powder mixture are essentiallyheterocyclic hydrocarbon based compounds such as toluene, xylene,benzene, tetrahydrofuran, cyclohexanone, quinoline and pyridine amongothers. Vacuum distillation can also be used in unit 65, alone or incombination with a second deasphalting step, to remove any remaininglighter molecules that could create voids in the carbon fiber. Anylighter material evolved in the vacuum distillation or similar processwill end up as stream 66. In addition, sparging can be considered withinunit 65 to produce more mesophase material by removing lightercomponents and altering the orientation of the carbon molecules topromote high performance carbon fiber in stream 130. Sparging is aprocess similar to air blowing, and for carbon fiber, it is normallyconducted with inert nitrogen instead of air.

Carbon fibers can be graphitized in unit 105 after carbonization in unit100 at temperatures close to 3,000° C. in an non-oxygen environment forimproved Young's modulus. This step can create high performance carbonfibers with tensile strength above 1.5 GPA (preferably above 3 GPa) andYoung's modulus above 290 GPA, up to 500 GPa. Stream 103 from unit 100is directed for graphitization in unit 105, while stream 101 is directlyset to the final step of surface treatment to create general purposecarbon fiber. The material leaving unit 105, graphitization, as stream108, will be high performance carbon fiber, stream 130, after surfacetreatment is performed in unit 110.

In one aspect, the feedstock 5 can be a heavy hydrocarbon (virgin or apreviously processed stream), such as the heavy hydrocarbon obtainedfrom a SAGD (steam assisted gravity drainage) process, for exampleCanadian Oil sands bitumen, or from any other suitable source of heavyhydrocarbon. In another aspect, the feedstock 5 can have an API gravityin the range of 0 to 14.

The thermal cracker, 30, in FIGS. 1 and 30 and 35 in FIG. 2, is operatedat conditions that maximize the economic return for producing bothpipelineable crude, 200, and carbon fiber products, 120 and 130. In oneaspect, the heater 20 will heat the process fluid 5 to a temperaturebetween 675-790° F. (357.2-421.1° C.). before the process fluid 25 isintroduced into the reactor 30. In the reactor 30, the process fluid 25(heated to 675-790° F. (357.2-421.1° C.) by the heater 20) undergoes amild controlled cracking process. Appropriately located heaters areprovided in this reactor 30 to maintain the desired constant temperaturegenerated in heater 20 and to apply uniform heat flux for the fluid. Theheaters provide indirect heat through any source readily available(electric, heat transfer fluid, radiant etc.). To ensure a uniform heatflux, mixing can be applied to the process fluid on a continuous orintermittent basis.

The reactor 30 can be operated in a manner, through optimizing primarilyfive inter-related process variables (Temperature, Pressure, ResidenceTime, Sweep Gas and Heat Flux), so as to reduce or even prevent cokefrom forming during the reaction, and minimizing gas production, whilealso providing optimal conversion of the asphaltene portion of the heavyhydrocarbon to provide the desired mix of refinery-ready feedstockcomponents through pipelineable crude and carbon fiber products.

The first and second variables involve applying a uniform heat fluxbetween 7000-12000 BTU/hr sq.ft (22.1-37.8 KW/m²) to the entire pool ofprocess fluid in the reactor and maintaining a single operatingtemperature in the reactor between 675-790° F. (357.2-421.1° C.). Thismay be achieved by the presence of appropriately sized and locatedheating devices in the reactor. The number of heaters will be set bycalculating the optimal dispersion of heat between any two heaters so asto have a uniform temperature throughout the pool and to avoid peak orspot temperatures significantly higher than the target temperature inthe reactor. Avoiding peak temperature spots reducing the chance forgenerating coke in the reactor.

The third reactor variable, residence time, can be between 5 up to 7hours minutes in the reactor. AS the residence time is increased, theconversion of 975+° F. (523.9+° C.) material to 975−° F. (523.9+° C.)material increases and the expected concentration of mesophase materialincreases.

The fourth reactor variable, operating pressure, can be maintained atnear atmospheric pressure, in any case, to be less than 50 psig (345kPa), with standard pressure control principles used for consistentperformance. The pressure range is controlled on the low end to preventexcessive, premature flashing of hydrocarbon, essentially bypassing thereactor, and limited on the high end to reduce secondary cracking andconsequent increased gas yields.

The fifth reactor variable, sweep gas 31, may be added to the processfluid in the reactor 30 in the range of 0-80 scf/bbl (0-14.24 Sm³/Sm³)if deemed beneficial to improving the reactor performance.

The sweep gas 31 can be natural gas, hydrogen, produced/fuel gas fromthe process, steam, nitrogen or any other non-reactive, non-condensablegas that will not condense to a liquid.

Sweep gas in the dosage of 0-80 scf/bbl (0-14.24 Sm³/Sm³) of feed may beprovided to remove the “lighter” hydrocarbon products (i.e. methane to<750° F. (398.9° C.)) boiling point hydrocarbons) as soon as they areformed in the reactor 30 so that there is a minimum of secondarycracking which could increase gas make and potentially increase olefinicnaphtha/distillate production. The sweep gas may also allow the reactorto operate closer to the desired operating pressure (<50 psig (345 kPa))and temperature. The sweep gas 31 can also be used to provide additionalheat and/or mixing to the process fluid 14 in the reactor 30.

Each variable may be changed independently, within the ranges suggested,based on the quality of feedstock provided or based on the quality andquantity of each output desired. Since the 5 noted process variables areinter-related, a multi-variable process control scheme with a prescribedobjective function (maximum yield to meet minimum productspecifications) will be beneficial to ensure the process operates at anoptimal point when any one of the variables is changed or thefeed/product situation is altered.

The overhead fraction 32 can be directed to a gas liquid separation unit40, which can comprise a cooler and separation drum, as an example, inwhich a portion of the overhead fraction 32 that is a condensable liquidproduct containing naphtha and heavier hydrocarbons can be separatedfrom the gaseous components of the overhead fraction 32. An off-gas line43 containing undesirable gases such as sour gas, can be provided at theseparation drum in unit 40 (not shown) for those gases to be disposedof, recycled, or subjected to further treatment.

One or more liquid hydrocarbon streams can be produced from separationdrum (not shown, but in 40).

The bottom fraction 32 can contain hydrocarbons, and thermally modifiedasphaltenes. Although the characteristics of the bottom fraction 32taken from the reactor 30 will vary depending on the process fluid 25input into the reactor 30 and the reactor's operating parameters, in oneaspect the bottom fraction 32 can have an API gravity ranging between −5and 5.

Controllable process variables allow an operator to vary the performanceof the reactor 30 to meet the needs of the final product based onchanging characteristics of the incoming process fluid 25.

The controllability of the five inter-related variables, residence time,sweep gas, heat flux, temperature and pressure in the reactor 30 allowan operator to vary the performance of the reactor 30.

In this manner, when the characteristics of the feedstock 5 are changedthe five inter-related process variables can be optimized to avoid theproduction of coke and minimize the production of non-condensable vaporswhich are produced in the reactor 30. For example, the operator can varythe residence time of the process fluid in the reactor 30 based on thecharacteristics of the process fluid to obtain the desired yields and/orquality of the bottoms output 32, and the overhead output, 33.Alternatively, the operator can vary the sweep gas, temperature orpressure to achieve similar outcomes. The process variables areinter-related and the minimization of coke and avoidance of excess gasmake is challenging and is best determined by pilot operations.

The reactor 30 is operated in a manner that significantly limits andeven prevents the formation of coke and reduces gas production whileconverting asphaltenes into more suitable components for downstreamprocessing. Consequently, modified asphaltenes and other heavycomponents remain in the bottom fraction 32 that is removed from thereactor 30. To maximize the recovery of the desirable refinery feedstockcrude and to separate heavy components for carbon fiber production, thebottom fraction 32 from the reactor 30 must be further treated using,for example, a high performance solvent extraction process 50. Thetreatment of the bottom fraction 32 by solvent extraction process 50allows the reactor 30 and the solvent extraction process 50 to be usedin conjunction, to produce a suitable full range refinery feedstockcrude transported via pipeline without the need for transport diluentand a solid asphaltene product for carbon fiber production which caninvolve the following steps: extrusion, melt spinning, stabilization,carbonization, graphitization, surface treatment, and/or sizing. Asstated previously, optional thermal conditioning in Unit 35, andoptional solvent deasphalting in Unit 55, can be employed to generatedifferent quality crude and carbon fiber products.

Example

250 lbs/hr (113.4 kg/hr) of diluted bitumen at 22.4 API (918.8 kg/m³)(stream 5 in FIG. 1 or 2) were processed at a 15 barrel/day (2.4 m³/day)dilbit feed pilot plant. The diluent was removed from the bitumen and170.6 lbs/hr (77.4 kg/hr) of bitumen (stream 25 in FIG. 1 or 2) was fedto the thermal reactor. The bitumen has an API of 7.7 API (1015.5kg/m³). 141.6 lbs/hr (64.4 kg/hr) of pipelineable crude (stream 200 inFIG. 1 or 2) was produced at 19.1 API (938.5 kg/m³), 270 cSt, less than0.5 wt % olefins, and less than 0.5 wt % sediment and water. Theprocessed crude product meets pipeline specification. Of note, theprocessed crude measured a micro-carbon residue (MCR) of less than 6 wt%. 21.3 bls/hr (9.66 kg/hr) of 10-15 um diameter general purpose carbonfiber (stream 120 in FIG. 1 or 2) was created with a young Modulus ofover 28 GPa and ultimate strength of over 170 MPa. Approximately 4.3lbs/hr (1.95 kg/hr) of solid material (stream 64 in FIG. 2) was createdthat can be used in the solid fuels market, and 3.4 lbs/hr (1.54 kg/hr)of fuel gas (stream 43 in FIG. 1 or 2) was generated for reusing in theprocess.

Definitions

Carbon fiber—Fiber containing at least 92 wt % carbon, while the fibercontaining at least 99 wt % carbon is usually called a graphite fiber.

General purpose carbon fiber—Carbon fibers that have relatively lowtensile strength (less than 1 GPa) and low modulus (less than 100 GPa)respectively. Isotropic-pitch-based carbon fibers belong to this gradeand are used in applications that benefit from their low weight andbulkiness, e.g. thermal insulation for a high-temperature furnace,cement reinforcement and activated carbon fiber applications).

Graphene—Graphene is an atomic-scale hexagonal lattice made of a singlelayer of carbon atoms. It is the basic structural element of many otherallotropes of carbon, such as graphite, diamond, charcoal, carbonnanotubes and fullerenes.

Insolubles—Material that precipitates into or remains in the solid formwhen mixed with a solvent.

Mesophase—A phase of matter intermediate between a liquid and solid,referred to as liquid crystals.

Non-Newtonian fluid—A fluid that its viscosity (the gradual deformationby shear or tensile stresses) is dependent on shear rate or shear ratehistory. A Non-Newtonian fluid's viscosity can change when under forceto either more liquid or more solid.

Pipelineable crude—Heavy hydrocarbon with API less than or equal to 19(density >920 kg/m3), and/or more than 300 cst that requires someprocessing to meet pipeline specifications of greater than API 19(density <920 kg/m3), viscosity less than 300 cSt at referencetemperature, sediment and water less than 0.4 wt % and olefins less than1 wt % or non-detectable by the measurement tool used by thetransporter.

Transport hydrocarbon—Diluent, condensate, hydrocarbon with Boilingrange of butane to 550° F. nominally

Tensile strength—Measure of the amount of force with which a fiber canbe pulled before it breaks.

Young's modulus—Measure of a material's stiffness defined as the axialstress divided by the axial strain. The higher the modulus, the stifferthe material (i.e. the greater the stress necessary to causedeformation).

What is claimed is:
 1. A process for treating a heavy hydrocarbonfeedstock, comprising: thermally treating the hydrocarbon feedstock at atemperature ranging from 700° F. to 790° F. for a residence time rangingfrom 1 minute to 7 hours to produce a lighter hydrocarbon stream and aheavier hydrocarbon stream; solvent deasphalting the heavier hydrocarbonstream with a solvent to precipitate asphaltenes and form solidasphaltene precipitates and produce deasphalted oil; separating thedeasphalted oil from the solid asphaltene precipitates to produce asolvent-diluted deasphalted oil stream comprising at least a portion ofthe solvent and a slurry stream comprising the asphaltene precipitatesand residual solvent; separating the solvent-diluted deasphalted oilstream to produce a recovered solvent stream and a deasphalted oilstream; separating the slurry stream to produce a solid asphalteneparticulate stream and a recovered solvent stream; and processing thesolid asphaltene particulate stream to produce a carbon fiber precursor.2. The process of claim 1, wherein separating the slurry streamcomprises vaporizing the residual solvent to produce a vapour/solidmixture comprising vaporized solvent and the solid asphalteneprecipitates, and subjecting the vapour/solid mixture to inertialseparation.
 3. The process of claim 1, further comprising extruding thesolid asphaltene particulate stream to produce extruded asphaltenes. 4.The process of claim 3, further comprising: spinning the extrudedasphaltenes into a continuous thread of asphaltene thread woundable on aspool; stabilizing the asphaltene thread by heat treatment at 350° F. to550° F. for up to 1 hour to produce a stabilized asphaltene thread;carbonizing the stabilized asphaltene thread by heat treatment at 1823°F. to 3632° F. for up to 1 hour to produce a carbonized carbon fiber;and conditioning the carbonized carbon fiber to produce a carbon fiberproduct, wherein the conditioning comprises surface treating and sizingthe carbonized carbon fiber.
 5. The process of claim 4, furthercomprising graphitizating the asphaltene thread, wherein thegraphitizating comprises heating the asphaltene thread to over 5432° F.to produce a graphene product.
 6. The process of claim 4, furthercomprising spooling the asphaltene thread to obtain a spooled asphaltenethread, wherein the spooled asphaltene thread has a diameter of below 15μm and has less than 10% void space.
 7. The process of claim 1, furthercomprising condensing the lighter hydrocarbon stream to produce acondensed lighter hydrocarbon stream including olefins, and saturatingthe olefins in the condensed lighter hydrocarbon stream to produce acondensed olefin-saturated liquid.
 8. The process of claim 7, furthercomprising combining the deasphalted oil with the condensedolefin-saturated liquid to produce a pipelineable crude product.
 9. Theprocess of claim 1, wherein the carbon fiber precursor enablesproduction of a carbon fiber product having a tensile strength of atleast 150 MPa and a young modulus of at least 20 GPa.
 10. The process ofclaim 1, wherein the solid asphaltene precipitates have a size rangingfrom 20 μm to 300 μm.
 11. The process of claim 1, further comprisingseparating insolubles from the solid asphaltene particulate stream,wherein separating the insolubles comprises combining the solidasphaltene particulate stream with an insolubles-producing solvent toproduce the insolubles, and removing the insolubles from the solidasphaltene particulate stream.
 12. The process of claim 11, wherein theinsolubles-producing solvent is a heterocyclic hydrocarbon.
 13. Theprocess of claim 12, wherein the insolubles-producing solvent is one ormore of toluene, xylene, benzene, tetrahydrofuran, cyclohexanone,quinoline or pyridine.
 14. The process of claim 1, wherein the solventused for the solvent deasphalting is a mixture of C₅-C₈ hydrocarbons.15. The process of claim 1, further comprising processing at least aportion of the solid asphaltene particulate stream into activatedcarbon.
 16. A system for treating a heavy hydrocarbon feedstock,comprising: a thermal reactor configured to receive the heavyhydrocarbon feedstock and operable at a temperature ranging from 700° F.to 790° F. for a residence time of between 1 min and 7 hours to producea lighter hydrocarbon stream and a heavier hydrocarbon stream; a solventdeasphalting separator in fluid communication with the thermal reactorand configured to contact the heavier hydrocarbon stream with a solventto precipitate asphaltenes and form solid asphaltene precipitates, thesolvent deasphalting separator producing a solvent-diluted deasphaltedoil stream comprising at least a portion of the solvent and a slurrystream comprising the asphaltene precipitates and residual solvent; aninertial separation unit in fluid communication with the solventdeasphalting separator, the inertial separation unit being configured toseparate the slurry stream solids to produce a solid asphalteneparticulate stream and a recovered solvent stream; and a processing unitin fluid communication with the inertial separation unit to process thesolid asphaltene particulate stream and produce a carbon fiberprecursor.
 17. The system of claim 16, wherein the processing unitcomprises an extruder configured to extrude the solid asphalteneparticulate stream to produce extruded asphaltenes.
 18. The system ofclaim 17, further comprising a first heater configured to stabilize theextruded asphaltenes at 350° F. to 550° F. for up to 1 hour to produce astabilized asphaltene thread.
 19. The system of claim 18, furthercomprising a furnace configured to carbonize the stabilized asphaltenethread at 1832° F. to 3632° F. for up to 1 hour to produce a carbonizedcarbon fiber, the carbonized carbon fiber being subjectable to a surfacetreatment to produce a carbon fiber product.
 20. The system of claim 19,further comprising a second heater downstream of the furnace, the secondheater being configured to operate in a non-oxygen environment to heatthe carbonized carbon fiber to over 5432° F. to produce a grapheneproduct.
 21. The system of claim 16, further comprising a flashseparator downstream of the inertial separation unit to vaporizeremaining residual solvent and remove lighter molecules from asphaltenescontained in solid asphaltene particulate stream.
 22. A process forproducing a carbon fiber product, comprising: thermally treating ahydrocarbon feedstock at a temperature ranging from 700° F. to 790° F.for a residence time ranging from 1 minute to 7 hours to produce alighter hydrocarbon stream and a heavier hydrocarbon stream; solventdeasphalting the heavier hydrocarbon stream with a solvent toprecipitate asphaltenes and form solid asphaltene precipitates andproduce deasphalted oil; separating the deasphalted oil from the solidasphaltene precipitates to produce a solvent-diluted deasphalted oilstream comprising at least a portion of the solvent and a slurry streamcomprising the asphaltene precipitates and residual solvent; separatingthe slurry stream to produce a solid asphaltene particulate stream and arecovered solvent stream; extruding the solid asphaltene particulatestream to produce extruded asphaltenes; spinning the extrudedasphaltenes into a continuous thread of asphaltene thread; stabilizingthe asphaltene thread by heat treatment at 350° F. to 550° F. for up to1 hour to produce a stabilized asphaltene thread; carbonizing thestabilized asphaltene thread by heat treatment at 1823° F. to 3632° F.for up to 1 hour to produce a carbonized carbon fiber; and conditioningthe carbonized carbon fiber to produce the carbon fiber product.